diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 19d7db4563ac..143043cd2dcb 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1492,6 +1492,7 @@ int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb) struct sk_buff_head *list = &sk->sk_receive_queue; int rmem, err = -ENOMEM; spinlock_t *busy = NULL; + bool becomes_readable; int size, rcvbuf; /* Immediately drop when the receive queue is full. @@ -1532,12 +1533,19 @@ int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb) */ sock_skb_set_dropcount(sk, skb); + becomes_readable = skb_queue_empty(list); __skb_queue_tail(list, skb); spin_unlock(&list->lock); - if (!sock_flag(sk, SOCK_DEAD)) - INDIRECT_CALL_1(sk->sk_data_ready, sock_def_readable, sk); - + if (!sock_flag(sk, SOCK_DEAD)) { + if (becomes_readable || + sk->sk_data_ready != sock_def_readable || + READ_ONCE(sk->sk_peek_off) >= 0) + INDIRECT_CALL_1(sk->sk_data_ready, + sock_def_readable, sk); + else + sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); + } busylock_release(busy); return 0;